Index: head/sys/netinet/tcp_input.c
===================================================================
--- head/sys/netinet/tcp_input.c
+++ head/sys/netinet/tcp_input.c
@@ -1979,7 +1979,7 @@
 				tp->t_flags |= TF_ACKNOW;
 
 			if (((thflags & (TH_CWR | TH_ECE)) == TH_ECE) &&
-			    V_tcp_do_ecn) {
+			    (V_tcp_do_ecn == 1)) {
 				tp->t_flags2 |= TF2_ECN_PERMIT;
 				TCPSTAT_INC(tcps_ecn_shs);
 			}
Index: head/sys/netinet/tcp_stacks/rack.c
===================================================================
--- head/sys/netinet/tcp_stacks/rack.c
+++ head/sys/netinet/tcp_stacks/rack.c
@@ -6296,7 +6296,7 @@
 		}
 
 		if (((thflags & (TH_CWR | TH_ECE)) == TH_ECE) &&
-		    V_tcp_do_ecn) {
+		    (V_tcp_do_ecn == 1)) {
 			tp->t_flags2 |= TF2_ECN_PERMIT;
 			TCPSTAT_INC(tcps_ecn_shs);
 		}